TWI532925B - The manufacturing method of the fan in a fan filter unit - Google Patents

Description

Fan of fan filter unit manufacturing method

The present invention relates to a fan configuration for use in a fan filter unit (FFU) for supplying a clean air stream to a clean room.

In the clean room, the following contents are described in the fourth column, line 23, page 3 of the Japanese Patent Laid-Open Publication No. 2000-205621, "There is a wide variety of medicines used in the clean room, so the fan The material is more suitable for use with a metal material (such as aluminum or stainless steel) than a resin product that may be attacked by these chemicals." The fan used in the prior art is processed from aluminum, stainless steel, gold-plated steel, steel, etc. The finished product after painting is combined with a sheet metal processing of a metal plate at a thickness of 0.5 to 1.0 mm.

Further, as shown in FIGS. 4 to 5, a conventional fan is integrally formed with a main supporting member A, an auxiliary supporting member B, a blade member C, and a motor shaft engaging boss D. Among them, the main support member A has a concave portion at the center, and is viewed from a horizontal plane in a circular plate shape. The sub-support member B is annular and has the same outer circumferential diameter as the main support member A, while the inner circumferential portion is twisted and bent in the same direction as the concave portion of the main support member A. The blade member C is vertically disposed between the main/secondary supporting members A and B and is vertically disposed at an equal interval in an obliquely radial direction. However, since the blade member C needs to match the position between the primary/secondary supporting members A and B, The support piece c provided on the blade member C can be inserted through the through holes of the two support members A, B and bent and locked on the outer side, and then the ferrule E is used to push the engagement sleeve D toward the concave center card of the main support member A. As for the joint assembly, it requires a very skilled and complicated manufacturing process. In addition, the press forming of the fan and the assembly cost are, for example, a model with a shape of 390 ,, which requires a high cost of 10 to 20 million yen, and also generates The manufacturing cost of the fan is high.

Furthermore, in order to make the fan stably rotate and prevent the occurrence of vibration, it is very important to balance the overall weight of the fan without offset. The sheet metal fan assembled as described above tends to cause unevenness in weight balance due to skew during stamping or welding, or offset during assembly, and in order to correct the imbalance, it is necessary to use a balancer to rotate one by one. The amount of weight shift and the measurement of the position, and the opposite counterweight are fixedly assembled on the opposite side to eliminate the imbalance. The aforementioned balance adjustment project is also the main cause of labor waste and high production cost.

In addition, since the fan filter unit is assembled by a metal fan with a weight, vibration is generated by the weight of the fan itself during transportation, and this vibration will cause the components to shift and cause a new imbalance. , leading to the need to re-adjust the overall balance.

The fan is affected by the impact of its own weight, so that the bearing supporting the rotating shaft of the motor is worn out. This loss is greatly related to the excessive vibration generated when the fan rotates and the malfunction of the motor.

In addition, if the weight of the fan is heavier, the fan needs to reach a prescribed number of rotations, which requires a longer starting time, and in order to achieve the specified time in a short time. For the number of rotations, a large motor having a torque greater than the torque required for normal rotation must be used.

Furthermore, the fan-type rotating body is prone to vibration and noise problems at the same time as the centrifugal force is increased, and in order to solve this problem, the dynamic balance is adjusted, the weight is reduced, and the fan is excessively lightened to cause a new rotation. The problem of speed (number of rotation damage) is generated.

In addition, in order to be able to install a plurality of fan filter units in a ceiling of an environment such as a clean room, it is necessary to achieve the goal of weight reduction as much as possible.

The fan of the present invention controls the foaming rate of the particulate polystyrene particles to be 10% to 30%, so that the foamed particles are matured in the storage bin for a specific period of time to stabilize the pressure inside the foamed particles. It is formed by adding an additive type flame retardant which is incombustible to itself and is filled in a mold for fan molding, wherein the self-flammable additive type flame retardant is hexabromocyclododecane. Thereby, the aforementioned conventional technical problems can be solved.

Since the fan of the present invention is formed of foamed styrene, the cost of the initial investment can be greatly suppressed to less than one tenth of the cost of the general molding die, compared to the stamping type fan and the assembled fan of the sheet metal product, and because The use of expanded styrene, which is lower in price than the sheet metal material, can significantly reduce the manufacturing cost of the fan.

Further, since the fan is integrally molded by foaming styrene through foam molding or formed into two separate bodies which are easily joined, the production efficiency can be drastically improved. At the same time, in the case of extremely light weight, even due to heavy The imbalance of the quantity causes the offset, and does not have any adverse effect on the rotation. In other words, since the reduction of the centrifugal force is proportional to the rate of mass reduction, even if the imbalance of the center of gravity is unbalanced, it can be kept within the range of no influence. Therefore, the effect of saving the adjustment of the fan balance procedure is obtained.

By reducing the weight of the fan, in addition to reducing the vibration generated by the fan filter unit during transportation, the imbalance caused by the vibration offset can be prevented, and the loss of the bearing supporting the motor shaft can be avoided.

Further, in the case of the weight reduction of the fan, even if the size of the drive motor is reduced, the predetermined number of rotations can be achieved in a short time, and thus the effect of reducing the equipment cost and the rotating electricity cost can be achieved.

In addition, since the fan is formed of a large-sized foamed styrene having a sound absorbing effect, the effect of reducing wind noise and motor vibration can be reduced without transmitting a special shockproof structure. Moreover, since the fan is coated with an electroless nickel plating layer, it is possible to further enhance the resistance, oil resistance and heat resistance of the foamed styrene product, and prevent dusting of the foamed styrene due to damage. At the same time, it can avoid the scattering of harmful gases generated by self-expanding styrene, and provide the same long-term service life as conventional sheet metal products.

In the present invention, the fan of the fan filter unit is formed of foamed styrene having a foaming rate of 10% to 30% (dimension ratio of 1.1 to 1.3 times), and the entire surface of the fan is covered with an electroless nickel plating layer.

The fan is formed by foaming styrene, which can greatly reduce the molding manufacturing cost and material cost compared with the conventional sheet metal fan. At the same time, it is not necessary to make assembly and balance adjustment, and it can suppress the vibration during transportation to prevent new shock when it is extremely lightweight. Compared with the conventional one, it can also use a small motor to rotate, further, even under continuous operation. It also has sufficient strength and resistance, oil resistance and heat resistance equivalent to those of sheet metal fans.

Example 1

1 to 3 are schematic views of Embodiment 1. First, the raw material polystyrene of the foamed styrene is foamed by a hydrocarbon gas such as butane or pentane, that is, the polystyrene-polystyrene particles having a diameter of 1 mm are absorbed into the hydrocarbon gas. And contacting it with a high temperature steam of more than 100 degrees Celsius above 80 ° 90 degrees Celsius, so that the resin softens and melts while applying pressure to the particles to foam, and finally the foamed particles are fused by a particle method. In the mold 2, a fan 1 of expanded styrene (EPS) is integrally molded.

More specifically, the polystyrene particles which are prepared for foaming are put into a foaming machine, and the polystyrene particles are expanded by steam heating while stirring, and the foaming rate of the controlled particles is 10 in the foregoing step. The setting value of %~30% (volume ratio is 1.1 times to 1.3 times), and it is transferred into the mature storage bin to allow the granules to be aged for about 8 to 24 hours to stabilize the pressure inside the pellets, and then the polystyrene particles are filled. In the mold 2 for fan molding, the particles are fused to each other by steam to form a fan 1. Further, as the raw material polystyrene, an inflammable additive type flame retardant such as hexabromocyclododecane (HBCDD) may be added in advance to improve the flame retardancy of the expanded polystyrene itself.

Since the mold 2 integrally molds the fan 1 into the main support member 1a, Since the sub-supporting element 1b, the blade element 1c, and the motor shaft-engaging bushing 1d are formed, the integrally formed fan 1 can be obtained without any assembly work at the time of demolding.

Further, the main support element 1a, the motor shaft joint bushing 1d, the auxiliary support element 1b, and the blade element 1c may be divided into two equally divided bodies, and the divided body may be joined by means of connection and the like. . Either way, it is easier to assemble and avoid unnecessary skewing due to stamping or welding operations than conventional sheet metal fans.

Further, since the expansion ratio of polystyrene is set at 10% to 30%, it is possible to obtain a high-quality fan 1 which is as strong as an injection-molded plastic product and which has high precision in appearance. Further, since the fan 1 having a thickness equivalent to that of the conventional sheet metal fan can be formed, in particular, in the case where the blade member 1c can be formed, the fan 1 can completely utilize the aerodynamic characteristics of the conventional fan design. Moreover, if the expansion ratio of polystyrene is less than 10%, the precision of molding may be lowered due to the weakening of the fusion force between the polystyrene particles, and if the expansion ratio is higher than 30%, the minimum thickness during processing may be caused. Ascending, in the case of an increase in thickness, the shape of the blade element of the air flow end may not be smoothly manufactured. In addition, since the material is made of a material suitable for a low-foaming process, it is not necessary to use a mold 2 of a high-pressure-resistant material, and it can be produced at a low price at the same time in consideration of strength.

In addition, since the density of the raw material polystyrene of the foamed styrene is 1.05, the fan 1 made of foamed styrene molded by the foaming ratio of 10% to 30% can be compared with the fan made of stainless steel (alloy). The weight ratio is approximately 1/8 to 1/10, which is significantly lighter, compared to aluminum (alloy) fans. It can be lightweight with a weight ratio of about 1/3 to 1/3.5.

Next, the demolished fan 1 was placed in an electroless plating bath, and an electroless nickel plating layer 3 of 5 to 20 μm thick was plated. Electroless plating is transferred to metal ions by the oxidation of the reducing agent, so that the surface of the non-conducting material such as foamed styrene can pass through the electroless plating forming the metal film to achieve a good adhesion film. The effect, especially the nickel-phosphorus alloy (Nickel-Phosphorus) electroless nickel plating, can form a uniform thickness coating with high precision (±5%) even on a surface with a complicated shape like the fan 1, allowing one-piece molding The fan 1 not only has no weight balance, but also improves the surface hardness and has good corrosion resistance. Furthermore, since electroless nickel plating also has a high degree of ductility, it also has good tracking and recovery properties for slight deformation caused by the reaction of the reaction force when the fan is blown. In addition, the electroless nickel plating can simultaneously enhance the resistance and oil resistance of the foamed styrene weak point, prevent the dusting phenomenon caused by the appearance of foamed styrene, and the harmful gas emitted from the foamed styrene to be blown to The situation in the clean room. Furthermore, because of the improvement in heat resistance, it can also meet the flame retardancy qualification values specified in the fire protection law.

The fan 1 manufactured through the above steps is fitted to the motor shaft coupling boss D to the rotation shaft 5a of the motor 5 fixed to the module 4, and the fixing screw 6 is locked. Further, the module 4 is assembled to the outer casing to become the fan filter unit 8. By extremely reducing the weight of the fan 1, the motor 5 can be shortened to a predetermined number of rotations by using a specification smaller than that of the prior art. Moreover, by the weight reduction of the fan 1, in addition to preventing the unbalanced skew caused by the vibration generated during transportation and the damage of the motor bearing, it is further improved. In the step, since the fan is molded using foamed styrene having a strong sound absorbing property, the design can reduce the wind noise and the motor vibration even without using any special anti-vibration structure design.

The fan made of foamed styrene of the present invention can be widely applied to a novel fan filter unit or exchanged with an existing fan.

1‧‧‧fan

1a, A‧‧‧ main support components

1b, B‧‧‧ auxiliary support elements

1c, C‧‧‧ fan blade components

1d, D‧‧ ‧ Motor shaft joint bushing

2‧‧‧Molding

3‧‧‧ Electroless nickel plating

4‧‧‧Modular

5‧‧‧Motor

5a‧‧‧Motor rotation shaft

6‧‧‧ screws

7‧‧‧Outer box

8‧‧‧Fan filter unit

c‧‧‧Support

E‧‧‧ Rivets

1 is a longitudinal cross-sectional side view of a fan outer shape; FIG. 2 is a plan view of a fan plated with an electroless nickel plating layer; FIG. 3 is a longitudinal cross-sectional side view of the fan filter unit in a combined standing state; A longitudinal cross-sectional side view of the combination of the standing state of the fan; and FIG. 5 is a plan view of the combined standing state of the fan of FIG.

1‧‧‧fan

1a‧‧‧Main support element

1b‧‧‧Auxiliary support elements

1c‧‧‧Fan leaf element

1d‧‧‧Motor shaft joint bushing

2‧‧‧Molding

Claims (1)

A method for manufacturing a fan of a fan filter unit, wherein the fan supplies a clean airflow to the clean room, wherein the fan controls the foaming rate of the particulate polystyrene particles to be 10% to 30%. Foaming, after each foamed granule is matured in a storage bin for a specific period of time to stabilize the pressure inside each of the foamed granules, and then added to the flame-retardant additive-type flame retardant and filled into a mold for fan molding to form The additive flame retardant which is inherently flame retardant is hexabromocyclododecane.